/* Base styles */
:root {
    --primary-blue: #003767;
    --secondary-blue: #79bde8;
    --fall-color: var(--primary-blue);
    --fall-light: #e6eef4;
    --spring-color: var(--secondary-blue);
    --spring-light: #eaf6fd;
    --summer-color: #e67e22;
    --summer-light: #fef5ec;
    --winter-color: #8e44ad;
    --winter-light: #f5eef8;
    --may-color: #f1c40f; /* Yellow for May */
    --may-light: #fef9e7;
    --primary-text: #333;
    --secondary-text: #666;
    --border-color: #ddd;
    --border-radius: 4px;
    --transition-speed: 0.3s;
}

/* Use a CSS reset for consistent rendering */
*, *::before, *::after {
    box-sizing: border-box;
}

.container {
    margin: 0 auto;
    max-width: 1600px; /* Limit maximum width for better readability on large screens */
}

.container h1 {
    color: var(--primary-blue);
    margin-bottom: 20px;
}

/* Loading indicator */
.loading-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 20px 0;
}

.spinner {
    border: 4px solid rgba(0, 0, 0, 0.1);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border-left-color: var(--primary-blue);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Filters */
.filters {
    margin-bottom: 20px;
}

.filters h2 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: var(--primary-blue);
}

.filter-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 20px;
}

.filter-buttons button {
    padding: 8px 16px;
    border: none;
    background-color: #e0e0e0;
    cursor: pointer;
    font-size: 1rem;
    transition: all var(--transition-speed) ease;
    border-radius: var(--border-radius);
}

.filter-buttons button:hover {
    background-color: #d0d0d0;
}

.filter-buttons button.active {
    background-color: var(--primary-blue);
    color: white;
}

/* Semester-specific colors - use CSS variables for consistency */
.filter-buttons button.spring {
    border-left: 4px solid var(--spring-color);
}

.filter-buttons button.summer {
    border-left: 4px solid var(--summer-color);
}

.filter-buttons button.fall {
    border-left: 4px solid var(--fall-color);
}

.filter-buttons button.winter {
    border-left: 4px solid var(--winter-color);
}

.filter-buttons button.may {
    border-left: 4px solid var(--may-color);
}

/* Location filters */
.location-filters button[data-location="online"] {
    border-left: 4px solid #2ecc71;
}

.location-filters button[data-location="on-campus"] {
    border-left: 4px solid var(--secondary-blue);
}

/* Search styles */
.search-container {
    margin-bottom: 20px;
    display: flex;
    gap: 10px;
}

.search-input {
    flex: 1;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
}

.search-button, .clear-button {
    padding: 8px 16px;
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: background-color var(--transition-speed) ease;
}

.search-button {
    background-color: var(--primary-blue);
}

.search-button:hover {
    background-color: #002a4e;
}

.clear-button {
    background-color: #6c757d;
}

.clear-button:hover {
    background-color: #5a6268;
}

.search-highlight {
    background-color: yellow;
    padding: 2px;
}

/* Calendar table styles */
.calendar-container {
    overflow-x: auto;
    margin-bottom: 20px;
    background-color: white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    border-radius: var(--border-radius);
}

.calendar-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed; /* Improves rendering performance */
}

.calendar-table th {
    background-color: var(--primary-blue);
    color: white;
    padding: 12px;
    text-align: left;
    position: sticky;
    top: 0;
    z-index: 1; /* Ensure headers stay above content when scrolling */
}

.calendar-table td {
    padding: 12px;
    border-bottom: 1px solid #e0e0e0;
    word-wrap: break-word; /* Prevent text overflow */
}

.calendar-table tr:hover {
    background-color: rgba(0, 0, 0, 0.05);
}

.text-center {
    text-align: center;
}

/* Semester color coding - use CSS variables */
tr.spring {
    background-color: var(--spring-light);
    border-left: 4px solid var(--spring-color);
}

tr.summer {
    background-color: var(--summer-light);
    border-left: 4px solid var(--summer-color);
}

tr.fall {
    background-color: var(--fall-light);
    border-left: 4px solid var(--fall-color);
}

tr.may {
    background-color: var(--may-light);
    border-left: 4px solid var(--may-color);
}

tr.winter {
    background-color: var(--winter-light);
    border-left: 4px solid var(--winter-color);
}

/* Location indicators */
.location-badge {
    display: inline-block;
    padding: 3px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: bold;
    text-transform: uppercase;
}

.location-online {
    background-color: #2ecc71;
    color: #074d24;
}

.location-campus {
    background-color: var(--secondary-blue);
    color: var(--primary-blue);
}

/* Page size selector */
.page-size-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.page-size-selector label {
    margin-right: 10px;
}

.page-size-selector select {
    padding: 5px;
    border: 1px solid #ccc;
    border-radius: var(--border-radius);
}

/* Pagination styles */
.pagination {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 20px;
}

.pagination-button {
    padding: 8px 16px;
    background-color: var(--primary-blue);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: background-color var(--transition-speed) ease;
}

.pagination-button:hover {
    background-color: #002a4e;
}

.pagination-button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

.pagination-info {
    font-size: 0.9rem;
    color: var(--secondary-text);
}

#location-h2 {
    margin-top: 2rem !important;
}

/* Mobile responsiveness - use a mobile-first approach */
@media (max-width: 768px) {
    .filter-buttons {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-buttons button {
        margin-bottom: 5px;
    }
    
    .search-container {
        flex-direction: column;
    }
    
    .search-button, .clear-button {
        width: 100%;
    }
    
    .calendar-table {
        display: block;
    }
    
    .calendar-table thead {
        display: none; /* Hide table headers on mobile */
    }
    
    .calendar-table tbody {
        display: block;
    }
    
    .calendar-table tr {
        display: block;
        margin-bottom: 15px;
        box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
        border-radius: var(--border-radius);
        overflow: hidden;
    }
    
    .calendar-table td {
        display: block;
        text-align: left;
        padding: 10px 15px;
        position: relative;
        border-bottom: 1px solid #eee;
    }
    
    .calendar-table td:before {
        content: attr(data-label);
        font-weight: bold;
        display: block;
        margin-bottom: 5px;
        color: var(--primary-blue);
    }
    
    .pagination {
        flex-direction: column;
        gap: 10px;
    }
    
    .pagination-info {
        order: -1;
        margin-bottom: 10px;
    }
    
    .pagination-button {
        width: 100%;
    }
}

/* Print styles for better printing */
@media print {
    .filters, .search-container, .page-size-selector, .pagination {
        display: none;
    }
    
    .calendar-table {
        border: 1px solid #000;
    }
    
    .calendar-table th {
        background-color: #eee !important;
        color: #000 !important;
    }
    
    .calendar-table tr {
        page-break-inside: avoid;
    }
    
    .location-badge {
        border: 1px solid #000;
    }
}